The present invention is concerned with new N-(2'-aminophenyl)-benzamide derivatives, a process for the preparation thereof, pharmaceutical compositions containing them, and the use thereof for combatting neoplastic diseases.
German Patent 33 05 755 describes compounds of the general formula I ##STR1## wherein at least one of R.sup.1 and R.sup.3 is a methyl radical and the other symbols R.sup.1, R.sup.2, and R.sup.3, which can be the same or different, represent hydrogen atoms or methyl radicals, as being effective for combatting malignant, proliferative, and autoimmune diseases, 4-amino-N-(2'-aminophenyl)-benzamide and its N-monomethyl derivative being said to be especially effective.
Surprisingly, we have now found that the basic p-amino function, which was initially thought to be pharmacologically essential, is not responsible for the therapeutic effectiveness of these compounds but rather that the absence thereof or a chemical change or thereof into neutral-reacting groups by substitution or replacement thereof by nonbasic radicals gives rise to effective compounds with a superior compatibility.